260 results match your criteria: "MacDonald Campus of McGill University[Affiliation]"

Quantitative determination of moisture in lubricants by Fourier transform infrared spectroscopy.

Appl Spectrosc

February 2004

McGill IR Group, Department of Food Science and Agricultural Chemistry, Macdonald Campus of McGill University, 21,111 Lakeshore Road, Ste. Anne de Bellevue, Quebec, Canada H9X 3V9.

This paper describes the development of a practical Fourier transform infrared (FT-IR) method for the determination of moisture in lubricants through the combined use of signal transduction and differential spectroscopy to circumvent matrix effects. The acid-catalyzed stoichiometric reaction of 2,2-dimethoxypropane (DMP) with moisture to produce acetone was used to provide IR signals proportional to the amount of moisture present in oils. Calibration standards were prepared by spiking polyalphaolefin (PAO) gravimetrically with water using dioxane as a carrier.

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Two strains of Colletotrichum coccodes, the wild type (DAOM 183088) and T-20a, engineered with the necrosis- and ethylene-inducing peptide (NEP1) gene for hypervirulence on velvetleaf (Abutilon theophrasti, Medik.), were monitored in planta for the first 2 weeks after infection. Real-time quantitative polymerase chain reaction (QPCR) was used to assess the extent of colonization of both strains on velvetleaf using SYBR Green chemistry.

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Jasmonates induce Nod factor production by Bradyrhizobium japonicum.

Plant Physiol Biochem

February 2007

Plant Science Department, Macdonald Campus of McGill University, 21,111 Lakeshore Road, Sainte-Anne-de-Bellevue, Que., Canada.

Jasmonates are signaling molecules involved in induced systemic resistance, wounding and stress responses of plants. We have previously demonstrated that jasmonates can induce nod genes of Bradyrhizobium japonicum when measured by beta-galactosidase activity. In order to test whether jasmonates can effectively induce the production and secretion of Nod factors (lipo-chitooligosaccharides, LCOs) from B.

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A washing procedure to mobilize mixed contaminants from soil: I. Polychlorinated biphenyl compounds.

J Environ Qual

January 2007

Department of Food Science and Agricultural Chemistry, Macdonald Campus of McGill University, 21,111 Lakeshore Road, Ste-Anne-de-Bellevue, QC, Canada H9X 3V9.

We conducted a laboratory study to assess the feasibility of a washing process with nonionic and anionic surfactants in combination with ethylenediaminetetraacetate (EDTA) for the simultaneous mobilization of heavy metals and polychlorinated biphenyls (PCBs) from a field-contaminated soil. Unit processes consisting of complexometric extraction and surfactant-assisted mobilization were combined with reagent regeneration and detoxification steps to generate innocuous products. Ten minutes of ultrasonic mixing of the soil with a combination of 30 mL L(-1) surfactant suspension and a sparing quantity (2 mmol) of EDTA mobilized appreciable quantities of PCBs, virtually all of the available Cd, Cu, Mn, and Pb, and lesser amounts of the Zn, Ni, and Cr but only small quantities of Al and Fe.

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A washing procedure to mobilize mixed contaminants from soil: II. Heavy metals.

J Environ Qual

January 2007

Department of Food Science and Agricultural Chemistry, Macdonald Campus of McGill University, 21,111 Lakeshore Road, Ste-Anne-de-Bellevue, QC, Canada.

We conducted a laboratory study to assess the efficiency of nonionic and anionic surfactants in combination with a sparing quantity of ethylenediaminetetraacetate (EDTA) to simultaneously extract heavy metals (HMs) and polychlorinated biphenyl (PCB) compounds from a field-contaminated soil. A soil wash that mobilized both HMs and PCBs was combined with back-extraction with hexane to remove PCBs from the aqueous wash. The aqueous washing suspension was then regenerated by precipitation of the HMs induced by corrosion and hydrolysis of zero-valent Mg to provide a cleaned soil and innocuous extract.

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A new method for culturing rodent whole embryos at the late organogenesis stage was developed using a roller-bottle system with intermittent gassing. Rat embryos were cultured for 24 h from gestational day (GD) 13.5 to 14.

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Whey protein isolates (WPI) may provide anti-inflammatory benefits to cystic fibrosis (CF), which could be mediated via peptides, as proteolytic digests of WPI enhance intracellular glutathione (GSH) concentrations. The objectives of this study were to investigate whether high hydrostatic pressure can (i) improve the in vitro digestibility of WPI; and (ii) generate low molecular weight (< 1 kDa) peptides from WPI hydrolysates that exert GSH-enhancing and anti-inflammatory properties in wild type and mutant CF transmembrane conductance regulator (CFTR) tracheal epithelial cells. Hydrostatic pressure processing enhanced the in vitro digestibility of WPI to proteolytic enzymes resulting in altered peptide profiles as assessed by CZE and GC-MS.

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Recent reviews indicate that pollutants in the surrounding macroenvironment directly influence the population dynamics, distribution and dispersal of fish ectoparasites, often leading to increased parasitism. The aim of the current study was to explore the effects of sublethal concentrations of waterborne zinc (up to 240 microg Zn/L) on survival, reproduction and morphometrics of Gyrodactylus turnbulli, a viviparous monogenean infecting the skin and fins of the guppy, Poecilia reticulata. Parasite survival and reproduction on the fish were recorded daily for individual parasites maintained in isolated containers.

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Alpha,beta-dicarbonyl reduction by Saccharomyces D-arabinose dehydrogenase.

Biochim Biophys Acta

November 2006

Department of Bioresource Engineering, Macdonald Campus of McGill University, 21 111 Lakeshore Road, Ste-Anne-de-Bellevue, Quebec, Canada H9X 3V9.

An alpha,beta-dicarbonyl reductase activity was purified from Saccharomyces cerevisiae and identified as the cytosolic enzyme D-Arabinose dehydrogenase (ARA1) by MALDI-TOF/TOF. Size exclusion chromatography analysis of recombinant Ara1p revealed that this protein formed a homodimer. Ara1p catalyzed the reduction of the reactive alpha,beta-dicarbonyl compounds methylglyoxal, diacetyl, and pentanedione in a NADPH dependant manner.

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Malacosoma disstria larvae are a pest of deciduous trees. Little is known on the interaction of bacteria with the immediate hemocytic antimicrobial responses of these insects. Incubating dead Xenorhabdus nematophila and Bacillus subtilis with a mixture of serum-free granular cells and plasmatocytes in vitro revealed differential bacterial-hemocyte adhesion and differential discharge of lysozyme and phenoloxidase but not total protein.

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Inhibition of IL-8 release from CFTR-deficient lung epithelial cells following pre-treatment with fenretinide.

Int Immunopharmacol

November 2006

School of Dietetics and Human Nutrition, Macdonald Campus of McGill University, 21,111 Lakeshore, Ste. Anne de Bellevue, Quebec, Canada H9X 3V9.

Cystic fibrosis (CF) is characterized by a biochemical abnormality in the cystic fibrosis transmembrane conductance regulator (CFTR) channel. CFTR-deficient lung epithelial cells may have high constitutive glutathione (GSH) levels that could decrease the intracellular content of the sphingolipid second messenger, ceramide. Altered ceramide levels in CF cells could, in turn, lead to their resistance to apoptosis and an immune hyper-responsiveness.

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Zeolite (clinoptilolite) as feed additive to reduce manure mineral content.

Bioresour Technol

December 2007

Department of Bioresource Engineering, Macdonald Campus of McGill University, 21 111 Lakeshore, Ste Anne de Bellevue, QUE, Canada.

Clinoptilolite (a species of zeolite) as grower hog feed additive can potentially improve nutrient ingestion and lower manure nutrient levels. A first objective was to establish the optimal particle size of the zeolite powder, as a fine size increases the adsorption surface while a coarse size can facilitate handling. The second objective tested the effect of feeding zeolite on manure nutrient levels.

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Traditional food consumption and nutritional status of Dalit mothers in rural Andhra Pradesh, South India.

Eur J Clin Nutr

November 2006

Centre for Indigenous Peoples' Nutrition and Environment, School of Dietetics and Human Nutrition, Macdonald Campus of McGill University, Ste-Anne-de-Bellevue, Quebec, Canada.

Objectives: To describe prevalence of malnutrition and their correlates of nutrient and traditional food consumption in rural Dalit mothers.

Design: In a cross-sectional study, we used socio-cultural questionnaires, anthropometric measurements and clinical eye examinations during the rainy season in 2003. Food frequency questionnaires and 24-h recalls were conducted during both summer and rainy seasons.

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Flavour-specific anticipatory hunger reinforced by either carbohydrate or protein.

Physiol Behav

June 2006

School of Dietetics and Human Nutrition, Macdonald Campus of McGill University, 21111 Lakeshore Road, Ste-Anne de Bellevue, QC, Canada H9X 3V9.

Recent evidence indicates that rats can learn to avoid aversive consequences of several hours of food deprivation by eating more of food having orosensory characteristics that predict a protracted fast. Two new studies tested if macronutrient composition of a flavoured meal before the reinforcing fast influences this acquisition of anticipatory hunger/satiety in a smooth-brained mammal. In one study, female Sprague-Dawley rats were trained for 11 cycles of 4 days with experimental meals of either carbohydrate or protein flavoured with either grape or cherry, with one odour followed by a 3-h fast and the other by 10 h of food deprivation.

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Monoamine oxidase (MAO) regulates levels of dopamine, serotonin, and noradrenaline in the nervous tissue and is required for proper neuronal development. The purpose of this study was to determine if oral exposure of adult female rats to methylmercury (MeHg) at 0.5 or 1 mg/kg/day before and during pregnancy would affect MAO activity in various brain regions of the offspring.

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High transmission rates restore expression of genetically determined susceptibility of mice to nematode infections.

Parasitology

May 2006

Institute of Parasitology, Macdonald Campus of McGill University, 21 111 Lakeshore Road, Ste-Anne de Bellevue, Quebec, Canada H9X 3V9.

This study investigated why the susceptible or resistance phenotype to the nematode Heligmosomoides polygyrus was lost when susceptible (C57BL/6) and resistant (Balb/c) strains of mice were housed together in indoor arenas with continuous transmission of the parasite larvae present in peat trays (Scott, 1991). First, both strains expressed their normal phenotype when given a controlled challenge while living in arenas, and when experimentally infected with only 5 parasite larvae. To test whether chronic exposure to peat altered the resistance phenotype, mice were given a challenge infection while living on peat.

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Nod factor induces soybean resistance to powdery mildew.

Plant Physiol Biochem

March 2006

Department of Plant Science, Macdonald Campus of McGill University, 21, 111 Lakeshore, Sainte-Anne-de-Bellevue, Que., Canada H9X 3V9.

Plants possess highly sensitive perception systems by which microbial signal molecules are recognized. In the Bradyrhizobium-soybean (Glycine max (L.) Merr.

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A new Fourier transform infrared method for the determination of moisture in edible oils.

Appl Spectrosc

October 2005

McGill IR Group, Department of Food Science and Agricultural Chemistry, Macdonald Campus of McGill University, 21,111 Lakeshore Road, Sainte-Anne-de-Bellevue, Quebec, Canada H9X 3V9.

Article Synopsis
  • A new method using Fourier transform infrared (FT-IR) spectroscopy has been developed to quickly and accurately measure moisture in edible oils by extracting water into dry acetonitrile.
  • A calibration curve was created using mid-infrared (MIR) spectra of moisture standards, allowing for precise measurement of water in oil samples through differential spectra.
  • The method has been validated against various oils and contaminants, demonstrating high accuracy (around +/-10 ppm) and offering a reliable alternative to the traditional Karl Fischer technique for analyzing moisture in edible oils.
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The effect of waterborne zinc (Zn) on Gyrodactylus population dynamics was studied on isolated guppies maintained at concentrations ranging from 0 to 240 microg Zn/l. After 1 week pre-exposure to Zn, each fish was experimentally infected with 3 gyrodactylids and parasite numbers were recorded daily on each fish until the fish either died or recovered from infection. Parasite establishment was most successful at 0 and 240 microg Zn/l (97%) compared with the intermediate Zn concentrations.

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Catalytic hydrogenation of polycyclic aromatic hydrocarbons over palladium/gamma-Al2O3 under mild conditions.

J Hazard Mater

November 2005

Department of Food Science and Agricultural Chemistry, Macdonald Campus of McGill University, 21,111 Lakeshore Road, Ste-Anne-de-Bellevue, Qué., Canada H9X 3V9.

As a prelude to the optimization of a continuous decontamination system, catalytic hydrogenations of selected tri-, tetra- and penta-cyclic aromatic hydrocarbon compounds over commercial alumina supported palladium were investigated under mild conditions ( approximately 90 degrees C/0.42 MPa H2) and interpreted in the light of reports from the literature. Acenaphthylene, acenaphthene, anthracene, phenanthrene, chrysene and benzo[alpha]pyrene were hydrogenated, virtually completely, to saturated polycyclic hydrocarbon compounds with no appreciable evidence of carbon-carbon bond rearrangement during equilibration.

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Zinc and copper uptake by plants under two transpiration rates. Part I. Wheat (Triticum aestivum L.).

Environ Pollut

December 2005

Department of Agricultural and Biosystems Engineering, Macdonald Campus of McGill University, 21 111 Lakeshore, Ste Anne de Bellevue (Quebec) H9X 3V9, Canada.

To evaluate the environmental risk of irrigating crops with treated wastewater, an experiment was conducted using two growth chambers, each offering a different vapour pressure deficit (VPD) for high and low transpiration rates (TR), respectively. One of the two sets of 24 pots planted with 6 week old wheat (Triticum aestivum L.), was placed in each growth chamber, and irrigated in triplicates for 20 days with 8 Zn and Cu solutions (0 and 25 mg Zn/L combined with 0, 5, 15 and 30 mg Cu/L).

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Zinc and copper uptake by plants under two transpiration rates. Part II. Buckwheat (Fagopyrum esculentum L.).

Environ Pollut

December 2005

Department of Agricultural and Biosystems Engineering, Macdonald Campus of McGill University, 21 111 Lakeshore, Ste Anne de Bellevue (Québec) H9X 3V9, Canada.

To evaluate the environmental risks of irrigating crops with treated wastewater, a study was undertaken to quantify heavy metal uptake by 4-week old buckwheat (Fagopyrum esculentum L.) plants during 18 days of irrigation with 8 different Cu and Zn solutions under two transpiration rates (TR). At 4 weeks, potted buckwheat plants were transferred into one of the two growth chambers, offering either a high or low vapour pressure deficit (VDP) for, respectively, a high or low TR.

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Dietary nutrients and anthropometry of Dene/Métis and Yukon children.

Int J Circumpolar Health

April 2005

Centre for Indigenous Peoples' Nutrition and Environment (CINE), and School of Dietetics and Human Nutrition, Macdonald Campus of McGill University, Quebec, Canada.

Objective: To describe nutrient intakes and anthropometry of 10-12-year-old Dene/Métis and Yukon children in the Canadian Arctic.

Study Design: 24 h-recall interviews (n = 222 interviews) were conducted on Canadian Dene/Métis and Yukon children in five communities during two seasons in 2000-2001; the children were measured for height and weight (n = 216).

Methods: Assessment of nutrient adequacy used Dietary Reference Intakes (DRIs) including cut-point procedures.

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Food use of Dene/Métis and Yukon children.

Int J Circumpolar Health

April 2005

Centre for Indigenous Peoples' Nutrition and Environment (CINE), and School of Dietetics and Human Nutrition, Macdonald Campus of McGill University, Quebec, Canada.

Objective: To describe food use of Dene/Métis and Yukon children with focus on food sources--traditional food (TF) and market food (MF), season, gender and location.

Study Design: Children of 10-12 years of age were interviewed for 24-h recalls (n = 222 interviews) in five communities during two seasons in 2000-2001.

Methods: Differences in children's food and nutrient intakes when consuming or not consuming at least one item of TF and across three regions were tested using ANCOVA after rank transformation of raw values.

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Cyclic AMP affects the haemocyte responses of larval Galleria mellonella to selected antigens.

J Insect Physiol

May 2005

Department of Natural Resource Sciences, Macdonald Campus of McGill University, 21,111 Lakeshore Road, Ste Anne de Bellevue, Quebec, Canada H9X 3V9.

Signal transduction of the innate immediate responses of insect haemocytes to foreign matter is rarely considered. Herein using a combination of adenylate cyclase inhibitors and activators and phosphodiesterase inhibitors we determined that cyclic adenosine monophosphate (cAMP) at high levels normally impairs non-self response. Haemocyte contact with glass and bacteria lowered cAMP in vitro.

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